Compounds containing boron and nitrogen



aired tine Patented Sept. 27, lace,

cooUNDs CONTAINING BoRoN AND Y NITROGEN v No Drawing. Filed Feb. 21, 1958, Ser. No. 716,542

3 Claims. or. 260-551 This application is a continuation-in-part of our copending applications Serial Nos. 647,934; 647,935; and 647,936, filed March 25, 1957, the last of the aforesaid applications having been abandoned in favor of the instant application. Application Serial No. 647,934 has N,N,N"-triphenylborazole.

now matured into Patent No. 2,892,869,. dated June where R represents a member of the class consisting of hydrogen and alkyl (including cycloalkyl), aralkyl, aryl, and alkaryl radicals, and R represents a monoethylenically unsaturated, aliphatic, hydrocarbon radicalc0ntai'ning at least 2 and not more than 4 carbon atoms.

Illustrative examples of hydrocarbon radicals" represented by R in the above formula are: methyl, ethyl, propyl, isopropyl, butyl, isobutyl', sec.-butyl, amyl, isoamyl, hexyl to tetracontyl, inclusive (both normal and isomeric forms), cyclopentyl, cyclohexyl, cycloheptyl, etc.; benzyl, phenylethyl, phenylpropyl, phenylisopropyl, phenylbutyl, fluorenyl, dinaphthylenemethyl, etc.; phenyl, biphenylyl or xenyl, naphthyl, anthryl, naphthyl-substituted anthryl and dianthryl, etc.; and tolyl, xylyl, ethylphenyl, propylphenyl, isopropylphenyl, butylphenyl, etc. Illustrative examples of radicals represented by R are vinyl, allyl, methallyl, propenyl, isopropenyl (fi-allyl), 1-butenyl, Z-butenyl (crotyl) and 3-butenyl. V

The new compounds of this invention range from liquids to semi-solids and solids in normal state. They are useful, for instance, as components of flame-resisting compositions; as plasticizers; as fuel additives; as crosslinking agents in resinous compositions; as scintillation counters; as the active ingredient in insecticides, bactericides, germicides, fungicides, pesticides, and the like; as

a chemical intermediate for use in the preparation of other compounds; as a component of arc-extinguishing tubes, and especially of surfaces that are exposed to the action of the are. They also can be employed alone or in combination with other substances that are copolymerizable therewith to yield new synthetic materials (homopolymers and copolymers) having particular utility in the plastics and coating arts. In any of these and other applications or uses, one can employ a. single compound of the kind embraced by Formulav I or a pluralityof. such compounds in any proportions. They can be used in conjunction with any of the conventional components of flame-resisting compositions, plasticizers, insecticides, bactericides, germicides, fungicides, pesticides, etc.

Preferred compounds of this invention are B,B,B"- trivinyl-N,N',N"-tripheny1bograzole and B,B',B"-triallyl- The formula for the firstnamed compound, which also may be named as ,B-tri; vinyl-N-triphenylborazole, is i |3H=CH HzC=HO-B I 05115 The formula for B,B,B"-triallyl-N,N,N"-triphenyl borazole, which also may be designated as B-triallyl-N- triphenylborazole, is

(111) lllHrOH=OHs V Haas-N NC5H6 HzC=HC-HzC-B B-CHzCH=CHg OsHr I Other'compounds embraced by Formula I that are within the scope of this invention (and which, for purpose of brevity, are named by the shorter nomenclature just indicated) include, for example, the following? Btrivinyl N-trixenylboraZol'e B-trimethallyl-N-tritolylborazole B-trivinyl-N-trimethylborazole B-triallyl-N-trimethylborazole B-tricrotyl-N-tribenzylborazole B-trivinyl-N-tri(methylcyclohexyl)borazole B-triallyl-N-tricyclohexylborazole B-trivinyl-N-trixylylborazole B-triallyl-N-trixylylborazole B-trivinyl-N-trieicosylborazole B-triallyl-N-trioctadecylborazole B-trivinylborazole, the formula for which is 7 (IV) ([3H=CH:|

Ht t lTT-H n2o=no-B B-on=orn N l i V t H t p 7 B-triallylborazole, the formula for which is (v) amma.

11-47 N41 H2C=HC-H2CB BCH2CH=C H2 solvent that is inert during the reaction, e.g., ether-s, di-

oxane, aromatic and aliphatic hydrocarbons, chloroben zone, etc. The trichloroborazole employed is one represented by the general formula where R has the same meaning as that given above with reference to Formula I.

The addition of the Grignard reagent to the suspension of the trichloroborazole can be carried out at temperatures of, for example, from about 1 or 2 C. up to the boiling point of the particular solvent employed. After addition of the Grignard reagent over a period of up to about 3 hours, e.g., from about /2 to 2 hours, is complete, the reaction mass is allowed to reflux or is kept at a temperature at or above room temperature for a period of from a few minutes to several hours. After cooling to room temperature (if not already at that temperature) the unconsumed Grignard reagent is removed by any suitable means, e.g., by treating the mass with a suitable material that will react with the excess Grignard reagent. One example of such a material is an aqueous solution of an acid, for instance HCl.

A preferred method of isolating the borazole compound involves the careful titration of the reaction mass with a saturated aqueous ammonium chloride solution to the point at which the magnesium salts separate from a clear solution of the reaction product. After decanting and washing the solid residue with ether, the combined solutions are dried over anhydrous magnesium 'sulfate for about 16 hours at refrigerator temperature (O5 C.), filtered, the filtrate concentrated by volatilizing the solvent, and methanol added to the hot solution until the latter becomes cloudy. After allowing this solution to stand at room temperature or lower, crystals of the product slowly form. Crystallization is completed by cooling to "-5 C. (or below 0 C: if necessary) for from several minutes to one hour. The product is then filtered and air-dried. It can be recrystallized from an ethermethanol mixture or from other suitable solvents or solvent mixtures.

In order that those skilled in the art better may understand how the present invention can be carried into effect, the following examples are given by way of illustration and not by way of limitation. All parts and percentages are by weight.

EXAMPLE 1 A. Preparation of B,B',B"-trichl0r0-N,N',N"- triphenylborazole A three-necked, 500 ml. flask equipped with stirrer, Dry-Ice condenser, and a Claisen head provided with a nitrogen inlet tube and a Drierite drying tube is charged with 200 ml. of toluene (freshly distilled over sodium or preferably calcium hydride) and cooled in an icewater bath while being swept with dry nitrogen. Boron trichloride (50 g.; 0.43 mole; slightly more than one equivalent to take care of slight loss due to hydrolysis) is distilled into the flask through the Dry-Ice condenser, causing a brownish-purple color to develop in the toluene solution. After replacing the drying tube with an addition funnel and protecting the exit of the condenser from moisture by a drying tube, a solution of aniline (30.4 g.; 0.326 mole) in toluene (100 ml.) is added dropwise with stirring over a one-hour period. An immediate precipitate of the addition compound separates from the purple-colored solution. The cooling bath is replaced by a heating mantle; the Dry-Ice con- 4 denser is also replaced by a water condenser, the outlet of which is connected by a rubber tubing to an inverted funnel held about 4 cm. above a beaker of water. The reaction mixture is then refluxed until evolution of HCl and BCl has ceased (24 hours). During this period the color of the solution changes from purple to a light brown. The solvent is slowly removed by distillation until the product begins to separate from solution. After allowing the mixture to cool to room temperature, the crystalline, almost colorless product is collected by rapid filtration. Yield: 32.6 g. (73%). A small portion recrystallized from dry benzene (filtered through glass wool) has M.P. 270272 C.; Jones and Kinney (I.A.C.S. 61, 1378 [1939]) report M.P. 265-270 C. Since the compound is quite susceptible to hydrolysis by moisture, it should be protected from moisture, e.g., by storing in a desiccator over a suitable drying agent or in a container to which enough benzene or toluene is added to wet the solid.

B. Preparation of B,B',B"-triallyl-N,N,N"- triphenylborazole Allyl magnesium bromide is prepared in, for instance, the following manner:

Allyl bromide (26.4 g.; 0.218 mole) in 50 ml. of ether is added to 5.3 g. (0.218 mole) magnesium turnings covered with 100 ml. of ether. Reaction starts immediately upon the addition of a crystal of iodine. After all of the allyl bromide has been added, the Grignard mixture is refluxed for 2 hours. A clear, ether solution of allyl magnesium bromide is obtained.

The above solution is added dropwise over a 45-minute period to 15.0 g. (0.0364 mole) B,B',B"-trichloro- N,N,N"-triphenylborazole (product of A) suspended in 100 ml. of anhydrous ether. A mushy solid replaces the suspended B-tn'chloro-N-triphenylborazole during the course of the addition. After adding all the Grignard reagent, the reaction mass is refluxed for 2 hours, after which the unreacted allyl magnesium bromide is decomposed with saturated aqueous ammonium chloride solution. The amount of ammonium chloride solution to be added is determined by the point at which the magnesium salts separate froman almost colorless, clear ether solution. After decanting and washing the solid residue with ether the combined ether solutions are dried over anhydrous magnesium sulfate for about 16 hours at refrigerator temperature. The ether solution is separated from the magnesium sulfate and concentrated to a volume of approximately 100 ml., at which point the solution is orange-yellow in color. Methanol is added to the refluxing solution until it becomes cloudy without depositing any crystalline material. After standing undisturbed at room temperature for several hours nicely formed, large crystals of product slowly separate from the solution. Precipitation is completed by placing the vessel containing the product in the refrigerator for about /2 hour or longer. The B,B',B"-triallyl-N,N',N"-triphenylborazole is collected by filtration and air-dried to give 12.2 g. of product (78% of theory); M.P. -98 C. Recrystallization from an ether-methanol mixture yields colorless crystals; M.P. 98-99 C. Analysis checks with the analysis of a sample of B,B',B"-triallyl- N,N',N"-triphenylborazole (prepared in essentially the same manner as that described above), M.P. 9899 C.,

Essentially the same procedure is followed as described under Example 1 in preparing and isolating other boractants and products are shown in TableL wliich follows.

From fair to good yields of product areobtained in the individual case.

aim-r1 The followingexample illustrates one use offthe" compounds ofthe present invention.

EXAMPLE 14 Ten (10) parts of B,B,B"-triallyl-N,N',N"-triphenylborazole is dissolved in 90'parts of benzene (in which it Example Halogenobnrazole Grlgnard Reagent Product 2 B,B,B"-trichloroborazole 'Methally'lmagnesium bromide; B,B,B"-trimetl1al1ylborazo1e. I 3 B,g3,13"1-trich1oro -N,N,N-t1'.iethyl- .Allyl magneslum brmide B,B',B" --trla1lyl -N,N',N triethyl- A orazo e. r I borazole. 4 B,B,B-trichloro-N,N',N"-trlt0lyl- -d0 B,B',B"-trlallyl-N,N','N"-tritolylborborazole. azole. 5 B,B,B -trlchloro -N,N,N -tricyclo- Propenyl magnesium bromide.-. B,B,B"-trtpropeny1-N,N',N"-trieycl0- hexylborazole. hexylborazole. 6 B,B,B-triehloro-N,N-N" -trlbenzyl- Allyl magnesium bromide B,B,B triallyl N,N',N" trlbenzyl borazole. borazole. 7 B,B,B-trichloro-N,N',N"-trlpheny1- Methallyl magnesium bromide" B,B,B-trimethallyl-N,N',N"-trlphenborazole. ylborazole.

EXAMPLE 8 is very soluble), and about 0.3 part of a 75% solution Preparation of BB,B,Ltrivinyl NN,,N" triphenyl of pmane hydroperoxide 1n pmane is added thereto. borazole The mixture is agltated to obtain a homogeneous solu- Vinyl magnesium bromide is prepared by slowly adding a solution of vinyl bromide (15.4 ml.; 0.218 mole) in tetrahydrofuran (50 ml.) to a suspension of magnesium (5.3 g.; 0.218 g. atom) in tetrahydrofuran (100 ml.). The resulting solution is then added dropwise over a 1 hour period to a suspension of 15 g. (0.0364 mole) of B-trichloro-N-triphenylborazole in 100 ml. of tetrahydrofuran. After refluxing for 1 /2 to 2 hours, the tetrahydrofuran is stripped oil under vacuum and the light brown solid which results is taken up in hot hexane. The hexane solution is washed with a small amount of water, dried, and concentrated to about 75 ml. A white, crystalline product comprising B,B',B-trivinyl-N,N',N- triphenylborazole is formed on cooling and this is collected by filtration. The mother liquor furnished additional product. Total weight: 6.3 g., yield: 51%.

The melting point of an analytical sample obtained by recrystallizing the less pure product from hexane is 174- 176 C.

Analysis:

Cale. IOrC HHB N percent 8.39 Fwmlpemnt 74177 6:47 "2335 11111 TABLE II tion, after which a portion is cast on a glass plate. The coated plate is placed in an oven maintained at about C. After about 6 hours at this temperature, homopolymerization of the monomer is evident. The resulting film of polymer is insoluble in benzene, which is a good solvent for the monomer.

The monomer used in this example, as well as other borazoles embraced by Formula I, can be copolymerized with other copolymerizable ingredients including, for example, (a) resins possessing a plurality of polymerizably reactive alpha,beta-enal groups, (b) compounds which are different from the borazoles of Formula I and which contain a CH C grouping, and (c) mixtures of (a) and (b). Specific examples of such copolymerizable ingredients are given in Patent No. 2,510,503, dated June 6, 1950, and in the patents referred to therein, and by reference thereto are made a part of this specification.

The compounds of this invention are unique in that they combine in one molecule a plurality of polymerizably reactive groupings attached directly to a 6-membered ring structure having both boron and nitrogen atoms in the ring. The advantages of such compounds in plastics, coating, laminating, adhesive, impregnating and other applications will be immediately apparent to those skilled in these arts.

In our copending application, Serial No. 716,541, filed concurrently herewith as a continuation-in-part of our copending application Serial No. 647,936, filed March 25, 1957, we have claimed homopolymers and copolymers of those borazoles embraced by Formula I wherein R represents the allyl radical, CH CH=CH and in the copending application of Joseph J. Pellon, Serial No. 716,559, also filed concurrently herewith, claims are made to certain copolymers of those borazoles embraced by Formula I wherein R represents the vinyl radical, CH=CHZ- Example Halogenoborazole Product B,B,B-trlchloroborazole 10 B,B,B trichloro N,N,N trlethyl borazole.

11 B,B,B" trichloro N,N',N" trltolyl borazole.

12 B,B',B -trichloro-N,N,N" -tribenzylborazole. bor

B,B,B trichloro N ,N',N tricyclohexylborazole.

azole.

13,13 ,B trivinyl N,N',N" tribenzyl .77 We claim: phatic, hydrocarbon radical containing at least 2 and not 1. Chemical compounds represented by the general m re than 4 Carbon toms. t a f ula 2. B,B',B"-trivinyl-N,N',N"-tripheny1borazo1e. R, 3. B,B,B"-trial1y1-N,N',N"-tripheny1borazole.

References Cited in the file of this;patcnt RlYI NR UNITED STATES PATENTS R'-B\ 1L3 2,821,463 Scott et a1. Ian. 28, 1958 12 OTHER REFERENCES Groszos et al.: Abstracts of Papers- American Chemiwhere R represents a member of the class consisting of l Society; 131 Megfing, April 7 12, 1957, Page 54 hydrogen and y afalkyl, W and i/ radicals, Wiberg et al.: Zeitschrift fiir Anorganische und Allgeand R represents a monoethylenically unsaturated, a1i- 15 m ch i 1 257, 139 (194g 

1. CHEMICAL COMPOUNDS REPRESENTED BY THE GENERAL FORMULA 